How to spawn an object on collision in box2d + love2d?

Question

I'm trying spawn collidable debris from a ship when it explodes in love2d/box2d, however, World:isLocked() is true when collision callbacks are called:

This will return true inside the callbacks from World:setCallbacks. (source)

So creating a new body throws an error. Are there any workarounds for this?

Answer 1

The usual way to solve this is to create the objects once the physics-simulation has completed.

In your collision callback you would push all the objects you want to create into a list-like data-structure. Once your physics-simulation-step is complete (eg. after world:update), create the objects/bodies that have been pushed to the list (thereby removing them from the list, so that they don't get created multiple times).